Roaring Fork River below Maroon Creek near Aspen
Roaring Fork River · Rockies · USGS gage 09076300
Coldwater (summer mean 11.9°C — prime coldwater).
Water
40°F
Flow
124 cfs
Air
44°F
Sky
100%
Pressure
29.98 in
Wind
7 mph
Predicted hatches · 2026-10-30
PredictedMidgeChironomidae0.50
Predicted by conditions; no reports yet. water 4.7°C (40°F) sits in the prime band (1-10°C); shoulder of the season; 8 days sustained ≥0°C; watch midday, especially cold months.
flies: Zebra Midge #18-22, Griffith's Gnat, Disco Midge
PredictedBlue-Winged OliveBaetis spp.0.40
Predicted by conditions; no reports yet. water 4.7°C (40°F) is warming toward the prime band (6-11°C); peak season; 8 days sustained ≥4°C; overcast skies favor it; watch midday, especially overcast afternoons.
flies: BWO Sparkle Dun #18-22, RS2, Pheasant Tail #18
PREDICTED from the first-principles model only. Report-confirmed signal (fly-shop & forum reports) is the next milestone.